Organic light emitting diode unit using an organic light emitting phenomenon is being widely applied to a variety of illuminators because it can achieve high luminance using low voltage and also applied to display devices because of a low driving voltage, thin-light weight, wide viewing angle, and high-speed response, etc.
The term “organic light emitting phenomenon” refers to a phenomenon in which electric energy is converted into light energy by means of an organic material. Specifically, when an organic layer is disposed between the anode and cathode and a voltage is applied between the electrodes, holes from the anode and electrons from the cathode are injected into the organic layer. Excitons are formed by combination of the injected holes and electrons and when the excitons drop to the ground state, light is emitted.
For example, an organic light emitting diode body including a bar-shaped first electrode or a first electrode formed on a support bar, an organic layer formed on the first electrode, and a second electrode formed on the organic layer is disclosed in Japanese Patent No. 2005-108643.
However, because the organic light emitting diode body is considerably sensitive to oxygen and water, performance and life of the organic light emitting diode body may be reduced by the permeation of oxygen and water. Accordingly, a cover layer is formed on the second electrode of the organic light emitting diode body to prevent permeation of oxygen and water.
The cover layer in the related art, however, is formed on the second electrode and covers only the second electrode, not the entire organic light emitting diode body, so that it is vulnerable to permeation of oxygen and water.